The role of sleep disorders in the risk for CKD and CKD progression.

Chronic kidney disease (CKD) is a major global health problem and an important driver of cardiovascular morbidity and mortality. Sleep disorders are highly prevalent in people with, or at risk of, CKD, but their specific contribution to CKD onset and progression has not been clearly defined. Unlike previous reviews that have focused mainly on symptom burden, quality of life, or general management of sleep problems in CKD, this narrative review is explicitly centred on renal outcomes. We examine whether common sleep disorders-insomnia, abnormal sleep duration, restless legs syndrome, periodic limb movement disorder, and obstructive sleep apnoea (OSA) and central sleep apnoea-are associated with an increased risk of incident CKD and with faster progression of established CKD [estimated glomerular filtration rate (eGFR) decline, albuminuria, end-stage kidney disease]. We synthesize evidence from prospective cohorts, administrative databases, and Mendelian randomization studies, with particular attention to residual confounding, incomplete sleep phenotyping, and overlap between sleep disorders, especially unrecognized OSA. Observational data suggest that poor sleep quality and abnormal sleep duration are modestly associated with incident CKD and CKD progression, although independence from OSA remains uncertain. In contrast, evidence linking OSA to reduced eGFR, albuminuria, and accelerated CKD progression is more consistent, and bidirectional relations between CKD and OSA are increasingly recognized. We also review pathophysiological pathways that plausibly connect sleep disorders to renal injury and critically appraise preliminary interventional data on OSA treatment and kidney outcomes. Finally, we outline the clinical implications of integrating outcome-oriented sleep assessment into nephrology and hypertension care and propose a research agenda to determine whether systematic detection and treatment of sleep disorders, particularly OSA, should be adopted as a strategy to prevent CKD onset and slow CKD progression.